<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <link href="css/bootstrap.min.css" rel="stylesheet"/>
    <script src="js/jquery-3.3.1.min.js"></script>
    <script src="js/bootstrap.min.js"></script>
    <style>
        div{
            width: 600px;
            height: 400px;
            border: 2px solid hotpink;
            float: left;
        }
    </style>
</head>
<body>
<h1>h1. Bootstrap heading</h1>
<h2>h2. Bootstrap heading</h2>
<h3>h3. Bootstrap heading</h3>
<h4>h4. Bootstrap heading</h4>
<h5>h5. Bootstrap heading</h5>
<h6>h6. Bootstrap heading</h6>
</body>
</html>